WINNIPEG, Manitoba -- Canadian emergency management officials in Manitoba say the Red River has reached a critical flooding stage for the capital city of Winnipeg.

The north-flowing river was at 20 feet Wednesday evening, prompting officials to partially open floodway gates to divert water around the city, the Winnipeg Free Press reported.

"The next 24 hours, perhaps the next 48 hours, are going to be absolutely critical," Steve Ashton, minister responsible for the Emergency Measures Organization, told reporters.

The biggest concern was over ice jams that restrict water flow south of the city, the report said.

Manitoba's two specialized Amphibex icebreaking machines are in the city, although one of them couldn't be launched Wednesday because a flatbed truck carrying it couldn't safely get to the riverbank, the Free Press said.

The Winnipeg Sun quoted officials as saying ice on the river usually can't sustain a flow of more than 45,000 cubic feet per second, although the flow Wednesday was nearly 50,000 cubic feet per second.